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Network Troubleshooting Questions

Practice questions for Network Troubleshooting topic in CompTIA Network+. 23 questions covering this domain.

23 questions6 easy10 medium7 hard
Q1
hard

A network engineer is reviewing interface statistics on a core switch. The interface shows a high number of CRC errors and runts but no collisions. Wh...

Q2
medium

During troubleshooting, a technician discovers that two hosts on the same VLAN cannot communicate. Checking the switch, the technician finds that one ...

Q3
easy

Which command-line tool sends ICMP echo request packets to a destination and reports whether the host is reachable and the round-trip time?

Q4
hard

After a network change, a technician follows the CompTIA troubleshooting methodology. After implementing a solution and verifying full functionality, ...

Q5
hard

Users on a remote branch site report intermittent slowness accessing the headquarters server. A network engineer captures traffic and observes high re...

Q6
easy

A technician uses `tracert` (Windows) to troubleshoot a connectivity issue. What does a row of asterisks (***) in the output indicate?

Q7
medium

A technician is troubleshooting intermittent network drops on a copper Ethernet cable run of 110 meters. The cable specification for Cat5e is a maximu...

Q8
medium

A technician uses `nslookup` to test DNS and receives a response with the server address but "Non-existent domain" for the queried hostname. What does...

Q9
hard

A technician troubleshooting a wireless client notices the client connects at a low data rate (54 Mbps) even though the AP supports 802.11ac. The clie...

Q10
medium

A technician runs `netstat -an` on a Windows server and sees multiple connections in the ESTABLISHED state on port 443 and several in TIME_WAIT. What ...

Q11
medium

A network administrator runs `ipconfig /all` on a Windows workstation and observes the IP address 169.254.45.12 with subnet mask 255.255.0.0. What doe...

Q12
easy

A user calls the help desk reporting they cannot access any websites but can ping other computers on the local network by IP address. What is the MOST...

Q13
easy

A technician wants to verify which TCP and UDP ports are currently listening on a Windows server and which processes are using them. Which command pro...

Q14
hard

An engineer is troubleshooting a site where users report the internet is slow but only for certain websites. `ping` to those websites shows high laten...

Q15
hard

A technician is troubleshooting a link that shows as up/up but is experiencing significant packet errors. The technician suspects a duplex mismatch. W...

Q16
easy

A user reports they cannot connect to any network resources. A technician checks the switch port and sees the port LED is solid amber. What does an am...

Q17
medium

A DHCP server log shows "address pool exhausted" errors. Users report they cannot get IP addresses. What is the MOST likely cause and immediate remedi...

Q18
hard

A network engineer troubleshoots an issue where hosts on VLAN 30 cannot reach hosts on VLAN 40 after a new Layer 3 switch configuration. The SVIs for ...

Q19
medium

After a configuration change on a router, a technician discovers that a specific subnet is no longer reachable. What should the technician check FIRST...

Q20
medium

A user reports intermittent VoIP call quality issues with choppy audio. The network team measures 2% packet loss and 180ms average latency on the WAN ...

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